Raise the Alarm

Create two 1/1 white Soldier creature tokens.

Silverflame Ritual

Put a +1/+1 counter on each creature you control.
Adamant — If at least three white mana was spent to cast this spell, creatures you control gain vigilance until end of turn.

Sunblade Samurai

Vigilance (Attacking doesn't cause this creature to tap.)
Channel — {2}, Discard this card: Search your library for a basic Plains card, reveal it, put it into your hand, then shuffle. You gain 2 life.

Luminous Phantom

Flying
Whenever another creature you control leaves the battlefield, you gain 1 life.
If Luminous Phantom would be put into a graveyard from anywhere, exile it instead.

Lunarch Veteran

Whenever another creature you control enters, you gain 1 life.
Disturb {1}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Lunarch Veteran // Luminous Phantom

Plains

Anointer Priest

Whenever a creature token you control enters, you gain 1 life.
Embalm {3}{W} ({3}{W}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Human Cleric with no mana cost. Embalm only as a sorcery.)

Celestial Unicorn

Whenever you gain life, put a +1/+1 counter on this creature.

Soul Warden

Whenever another creature enters, you gain 1 life.

Hand of Enlightenment

Era of Enlightenment

(As this Saga enters and after your draw step, add a lore counter.)
I — Scry 2.
II — You gain 2 life.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Era of Enlightenment // Hand of Enlightenment

Heron of Hope

Flying
If you would gain life, you gain that much life plus 1 instead.
{1}{W}: This creature gains lifelink until end of turn.